Adicionado frontendbr/vagas

[george-gca]

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• I am not the sole author or employee of a company who created either the topic I am modifying/adding or the collection entry I am modifying/adding.

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• Something that does not neatly fit into the binary options above

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Editing an existing topic or collection

I'm suggesting these edits to an existing topic or collection:

• Image (and my file is *.png, square, dimensions 288x288, size <= 75 kB)
• Content (and my changes are in index.md)

Added repo with Front-End work positions. Saw that it already had one for back-end, so this one was missing.